Detection of peptides, proteins and other biological analytes (“bioanalytes”) that are associated with a particular disease or pathological condition permits the diagnosis and prognosis of the disease or condition. For example, several cardiac marker proteins, such as acute coronary syndromes (ACS) and C-reactive protein (CRP), have been identified and are used for the diagnosis and prognosis of cardiovascular diseases.
Diagnostic tools used for detecting or quantifying bioanalytes typically rely on ligand-specific binding between a ligand and a receptor. Ligand/receptor binding pairs used commonly in diagnostics include antigen-antibody, hormone-receptor, drug-receptor, cell surface antigen-lectin, biotin-avidin, substrate/enzyme, and complementary nucleic acid strands. The bioanalyte to be detected may be either member of the binding pair; alternatively, the bioanalyte may be a ligand analogue that competes with the ligand for binding to the complement receptor.
A range of devices for detecting ligand/receptor interactions are known. For example, chemical/enzymatic assays are used in which the presence or amount of bioanalyte is detected by measuring or quantifying a detectable reaction product, such as gold immunoparticles. Ligand/receptor interactions can also be detected and quantified by radiolabel assays. Specifically, a frequently used assay method is enzyme linked immunosorbent assay (ELISA). Although very accurate, it is time-consuming, expensive, and technically complicated.
Biosensors that detect bioanalytes associated with wounds would be beneficial in the management of chronic wounds such as diabetic foot ulcers, pressure ulcers and venous leg ulcers. Management of these wounds is lengthy and challenging due to the inherent complexity of the biochemical processes occurring in non-healing wounds. Typically, regular examinations and assessments of the wound bed are performed by nurses and clinicians to inform the individual subject's wound treatment plan. This assessment process consumes a significant amount of nursing time and dressing materials, which contribute to increasing medical costs in wound care.
The use of advanced detection technologies, such as diagnostic and theranostic biosensors in wound management, especially for monitoring the healing status of acute and chronic wounds, is rapidly growing.[2, 6] The ideal diagnostic tool would afford a clear and simple read-out, not requiring interpretation from a medical expert, while a theranostic would release therapeutics in response to altered wound healing,[1, 2, 6] for instance as a result of bacterial infection.[7-9] It would be desirable for such diagnostic or theranostic biosensors to be incorporated into a wound dressing (a ‘smart’ dressing) or deployed as a point-of-care (POC) device that is fast, responsive and is both sensitive and selective.
There is a need for diagnostic tools that provide fast, sensitive, selective and/or low-cost detection of biomarkers of wound status or other diseases or pathological conditions.